In fact, most of the cables available are not keeping up to the standards and some are dangerous for your hardware. In worst case scenarios your charger/computer or even the phone could be damaged using those.
One of these potential dangerous adapters is sold by OnePlus as he pointed out.
The problem is, to my understanding, that a wrong resistor is used, urging to charge the device with 3A no matter what. If your charging device is not able to give that amount of power, it might get damaged. Normally, if the cable is compliant, this would be no problem. The power would be reduced to the correct and safe amount. Benson Leung is very clear on that:
"Don't buy this #USB #TypeC adapter for your Chromebook Pixel or Nexus 6P/5X phone. It uses the wrong identifier resistor."
Well, I think this is a big problem with USB-C. The specs are not "fail-safe". It seems much more complicated than with a standard USB-Cable were the handling of power is managed by the devices itself. You can easily plug a device that uses up to 2A on an old USB connector with 500mA. But these days seem to be gone. You need a safe cable not to ruin your devices. Maybe that's we manufacturers are not getting it. They need to realize that the devices with USB-C now relying on the cables. Well I'll guess nothing is perfect. Not even USB-C.